I'm willing to bet that with the cans opened up like that, there isn't much need for twin mufflers. I'm guessing again, but I think the main reason for the two was to get enough catalytic area to handle the flow, and they look cool too, on the street. Seems to me the SM crowd isn't that interested in a single system, but the TE guys like myself are very interested since they're heavy and up high. That and twin exhausts look funky offroad. Give Willie's recommendation a try if you would for all us TE guys and let us know if there is a drop in performance and increase in noise when one can is plugged up. Who knows, could be a money maker.
I might just do that soon, I'll be back out at the shop one or two days next week, I could fab up a quick clamp-on cap and see what happens...
Got my 2" SS perf pipe today. Gonna try tearing into it Sunday. My welder guy can fix any adaptors or connect rings to either end for the perf pipe. Gut cat, retain sparky. Going to keep the outlet end in tact. Got my pipe and packing from these guys, ordered it will-call: http://www.baronscustom.com/search/...ca2a978f&searchtype=products&query=perforated EDIT: I'm going to keep my twin cans because I like they way they look. If the flow is sufficient with one I might consider modifying the headpipe and capping off the second outlet/can. I'm not that concerned with weight at this point. It's already a middle-weight pig, so no biggie. Load it up with gear and go dualsporting.
A major success... Gutting the cat and stainless muffler dropped about 5lbs off and there is a noticeable surge of power at 3500-5000. Sound is a little more throaty but maybe only a DB or two over stock. Plus the cans stay cool enough to put your hand on them, the shields stay cool to the touch, except the screws that fasten them but that's to be expected. The rivets are easy to drill out with a 7/64 bit and then punch them in. The remaining rivet body drops into the inlet part of the muffler and they are easily removed once you cut off the front of the stainless muffler part. On the TE the whole outlet end cap is a one-piece unit. Once the star-screws are removed the end cap is easily tapped out with a screw-driver blade and hammer. Go easy here so you don't dent or scratch your end cap. Now the main body of the muffler can be tapped out the other way with a block of wood and a 3lb ballpene. With a hacksaw it's easy to cut the muffler part off and if you saw about 5/8" from the rivet flange on the inlet side you will get the complete cat as well. Look for the spot welds and saw just inside them, you'll retain the internal framing for the cat but your saw will take out the cat completely intact. You're left with an end cap with tapered inlet that the 2" perforated pipe fits right into. No punching, chiseling, or holesawing. It just cuts right off of the inlet cap assembly. I got 3' of pipe and used all but about 4" of it. This crap weighs 5lbs. With a ballpene hammer I tapped the end of the perf pipe so that the sparky just slides in. This holds the internal perf pipe nicely in place. No welding required, no special tools. The other end i did a much lighter taper so that it fit into the inlet end cap snuggly. The stainless piping from Baron's is really nice heavy duty stuff. Very nice to work with. The 3' length of pipe weighs less than 2lbs. I then wrapped the perf pipe with fiberglass muffler packing and spiral wound it with 20ga wire. The can housing is also lined with fiberglass. The whole thing fit back together easily and nicely. I used hi-temp RTV silicone on both fastening flanges of the end caps, aluminum rivets for the inlet, and re-used the star-end machine screws on the outlet. I now have a completely flow-thru cans with spark arrestors, plus the old girl dropped 5lbs in the process - Win-Win!! This thing just gets up and scoots now!
Wow. That looks just too easy to resist. The spark caps on the stock cans are nice -- they both muffle the sound and stop sparks. I would love to be able to keep them and still lose some heat and weight. Coupla questions -- You said the "can housing is also lined with fiberglass"...do you mean you lined it, or it is lined already? And -- what is inside those stock inserts laying there on your washer?
Nice job CJ, thanks for the in depth writeup and pics...I'll have to put this on the list of things to-do.
Excellent work on the pipes. I would suggest stainless steel rivits for longevity. I have heard a oval exhaust can flex out of shape when under load. Im not sure the aluminum rivits will tolerate the heat and flex.
I used aluminum rivets on both ends (SMS cans though) and they have held up fine for ~700mi. When they are flowthroughs, there is MUCH less retained heat and pressure inside the muffler, and the aluminum body is pretty dang beefy. Plus most cheap hand riveters will have trouble with 3/16" stainless rivets... :/
The catalytic coverters are at the left, the 2" cylinder thingies. The stainless muffler ovals are an internal baffle system. I doubt there's much back pressure to them but the inlet and outlet pipe for it is just 1", maybe even a bit less. I still like straight through though, at a full 2" except for the sparky and outlet. I can live with that. I'm sure that's why I got a power surge, it has to flow more exhaust now. The cans run cool enough now that you can lay your hand on them, just not for more than about 5 seconds. I would imagine they're at about 130-140deg. Seems to me before they were more like 150-180 before. If you cover one of the can openings it does quiet down a lot, so I suspect having the two really lets it breath, albiet at a weight cost of some 8lbs or so. I can live with that too. The stock housings are beefy, they are really a heavy duty piece. If the aluminum rivets blow out I'll have stainless ones installed or figure something else out. Maybe reinstall but drill in between them and install stainless screws as well. I don't think there's much pressure on them; I really don't think it's going to be an issue. Every couple of years remove the rear cap and re-pack them. There will be no need to remove the inlet cap again. Yes, I used a cheapo hand riveter with aluminum rivets it came with. Works really well, don't know what kind of strength though. I'm going to assume it's fine unless I find otherwise. My FMF Q4 on my KTM is just screwed together and the housing shell is super lightweight. No issues with it coming apart. When you compare an aftermarket can with the factory components they really do seem heavy duty. And yes, the stock aluminum housing is lined with an adhesive fiberglass matt. It insulates between the stainless muffler baffle and the outer housing. I put two layers of glass muffler batts around the perf pipe and it all packs in there pretty good. BTW, no ECU tweaks, just the power-up on mine. Runs clean and strong all the way through. I'll bet with a proper tune you could bump a few more ponies out of it. It's quite a rush as it is right now though - it's addicting. Makes me think 'Ducati' when I'm getting on it.
If interested in ss rivits and tool these are the ones I bought. tool: http://www.harborfreight.com/heavy-...and-riveter-with-collection-bottle-66422.html rivits: http://www.tractorsupply.com/home-i...teel-medium-length-rivet-3-16-in-dia--3895161
Hey, nice riveter. Too bad you're so far away, I could come by and borrow yours. EDIT: BTW, I got curious about rivets and looked up aircraft rivets and it looks like they are mostly aluminum: https://www.airpartsinc.com/shopdisplayproducts.asp?id=25&cat=Rivets I understand it's a different application, but still, if they're good enough for a flying wing they should be good enough for a muffler can. Aluminum sailboat masts also use aluminum rivets to fasten all the rigging hardware to them. Somehow I don't think there's going to be an issue with strength, but time will certainly tell.
That's what I keep coming back to. I've got the dual Leo's with the fragile plastic endcaps and plastic hangers. Then I look at the stock mufflers with the stainless endcaps and integrated super-duty hangers. I think, "Dang. Which setup would I want on the bike when I fall onto some rocks 5 or 6 times?" Yes, I know the endcaps and hangers are "carbon fiber." But...they're 95+% plastic resin (by weight and volume), with some carbon fiber reinforcement. They might hold together if they crack and break, but then they're still cracked and broken. It's the old engineering tradeoff: Light, strong or cheap. Pick any two. Leos: Light and cheap. Stock: Strong and cheap. Plus, the stockers have the uber-cool Husky logo designed into the outlets...
Oh, is that what that is??? I did not get that 'till now. Sometimes I'm a little thick. BTW, I measured the in/out on the baffle and they are 1-1/4". Not too bad. I'd still rather have 2".
The baffle is why they're so hot even with the cats removed. It's a no-maintenance setup (no repacking, ever) but the tradeoff is direct conductive contact to the thin bit of insulation and out to the casing. No airflow in between those pieces to carry away heat - it's a sealed cavity. Once it's hot, the insulation might as well not be there at all. It isn't doing anything without air running through it. If you can fit 2" tubing in there, you could also fit a piece of 1" inside that 2" tube up near the outlet to the spark cap. That would further reduce sound with practically nill effect on flow. Not that everybody wants it quieter, but I do.
Where have you guys been getting the 2" perfect pipe? Is that difficult to source? Cjbrown. Did you leave the internal ovals out when you reinstalled? Or weld them back on?
Just did this tonight the way CJBROWN did. One note I'll add - measuring 5/8" from the weld to cut the inlet side off puts you REALLY close to the extra baffle material inside the inlet. On one of the pipes I wound up cutting right at the baffle and it took forever and a saw blade to get through, little did I know I was cutting two and three layers at a time. The best and most consistent way to measure where to cut is to go 1 1/8" from the inside edge of the rivet holes. That way you cut right behind the baffle and at the start of the inside pipe.
I just want to chime in that I may be putting my cut-up OEM exhaust up for sale here in the next 2-3 weeks. I cut it for a slipon and now have the Leo system enroute. Perfect if you want a spare set of cans for gutting. You could also weld it back together where I cut it if you so desire.
